Adjusting and locking means for slidable jaw wrench



Jan. 10, 1956 w. A. BARNES 2,729,999

ADJUSTING AND LOCKING MEANS FOR SLIDABLE JAW WRENCH Filed Nov. 15, 1954 ,2 Sheets-Sheet l WILLIAM/4. BAR

INVENTO ATTORNEYS.

Jan. 10, 1956 w. A. BARNES 2,729,999

ADJUSTING AND LOCKING MEANS FOR SLIDABLE JAW WRENCH Filed NOV. 15, 1954 2 Sheets-Sheet 2 HIHI l||ll l l l w W/L L MM /4.BARNES INVENTOR.

A TTORNEYS'.

United States Patent '0 '1 2,729,999 ADJUSTING AND LOCKING MEANS FOR SLIDABLE JAW WRENCH William A. Barnes, Utica, N. Y., assignor to Utica Drop Forge & Tool Corporation, Utica, N. Y., a corporation of New York Application November 15, 1954, Serial No. 468,652

4 Claims. (Cl. 81-165) This invention relates to improvements in wrenches and more particularly in wrenches in which the movable jaw may be locked in adjusted position against accidental displacement.

One of the objects of the invention is to provide a wrench having an improved locking device of the character referred to, which is efiicient in operation and of simple and relatively inexpensive construction.

A further object of the invention is to provide an improved wrench with jaw adjusting means readily accessible at times when the usual adjusting worm is inaccessible.

A further object of the invention is to provide an improved wrench of simple construction in whichthe same actuating member may be used not only for adjusting the jaws of the wrench relative to each other, butalso to lock and unlock the movable jaw.

Further objects, features and advantages of the invention will appear more fully from the following detailed description taken in conjunction with the accompanying drawings illustrating several embodiments of the invention.

In the drawings, Fig. 1 is a side elevation of one embodiment of my improved wrench. Fig. 2 is a fragmentary side elevation of the same wrench with parts broken away. Fig. 3 is a section taken on line 33 of Fig. 2. Fig. 4 is an enlarged elevation showing the worm shaft and certain adjacent parts. Fig. 5 is a bottom plan view of Fig. 4. Fig. 6is a top elevation of the retaining spring forming part of the invention. Fig. 7 is a fragmentary view partially in elevation and partly in section, showing a modification of the wrench. Fig. 8 is a fragmentary view partially in elevation and partially in section showing another modification, and Fig. 9 is a section taken on line 9-9 of Fig. 8.

Referring to Figs. 1 to 6 inclusive, the wrench includes a handle which isprovided at one endthereof'with an enlargedhead 2. The head 2 is formed with a stationary jaw 3 which cooperates with movable jaw 4 which has a web portion 5 slideable in a slot formed in the head 2 in a manner Well understood in the art. The web 5 of the movable jaw is formed with the usual rack 6. The stationary jaw has a rectangular opening 7, in which a knurled worm S is supported so as to mesh with the rack 6, the worm 8 being supported in operative relation to the rack by a pin or shaft 9 having its axis parallel to the rack. Axial movement of the worm is prevented by the end walls of the opening 7, so that rotation of the worm shifts the rack and the movable jaw with respect to the stationary jaw in a well known manner.

The worm shaft 9, as shown, has an inner cylindrical bearing portion 10 supported in the fixed jaw for rotation and axial movement. The outer portion 12 of the shaft is supported in an aperture 13 in the fixed jaw. Theportion 12 ofthe shaft and the aperture 13 are so shaped that when the shaft is in its inner position, it is locked against rotation; it is free to rotate when it is in its outer position. To achieve this result, the outer portion 12 of the shaft is of any suitable splined construction, for example, of hexagonal cross section. The aperture 13 is formed with an inner splined portion. 14 which, as shown in Fig. 2, extends from the lower wall'of the opening 7 to the dotted line 15. To permit the ready insertionof the spline portion 12 of the shaft in the spline portion l4 of Patented Jan. 10, 1956 the aperture inlockingengagement, the splined aperture portion 14 is formed with a number of corners which is a multiple of the number of corners of the spline portion 12 of the shaft. For example, as shown in Fig. 3, the aperture is formed with 12 corners, so that the corners of the locking spline 12 engage in alternative corners of the aperture 14. In this manner, the shaft may be placed in locking engagement with the fixed jaw in numerous positions of adjustment of the shaft about its axis, for example, 12, in the exampleshown.

In order that the worm shaft may be free to rotate when the splined portion 12 of the shaftis moved downwardly out of engagement with the splined aperture portion 14, the portion of aperture 13 shown below the dotted line 15 in Fig. 21is formed of cylindrical cross section with a diameter substantially equal to the maximum diameter shaft portion.12, the portion of the worm shaft above thespline 12 being cylindrical and of reduced diameter as shown at 17, so as to be capable of freely turning within the splined aperture portion 14 when the shaft is in its lower or outer position. As the diameter of the outer cylindrical portion of the aperture 13 is substantially the same as the outer diameter of the splined portion 12 of the shaft, the walls of the aperture form a bearing surface for supporting the outer end of the worm shaft for adjustment and longitudinal movement.

It is desirable that the splined aperture portion 14 be formed directly in the fixed jaw of the wrench. This result may be achieved by first drilling through the fixed jaw a longitudinal aperture having a diameter equalto the minimum width or diameter of the splined portion 14 of the aperture. After this, the lower large cylindrical portion of the aperture 13 may be formed, as by drilling, whereupon the proper locking spline construction can be formed at 14 by a breaching operation with a tool movable through the aperture 13 in the direction of the axis of the worm shaft.

It is necessary that the worm 8 be mounted on the worm shaft 9 so as to permit sliding movement of the shaft through the center of the worm in a direction longitudinal of the shaft. At the same time, the worm in my invention is held against rotation with respect to the shaft regardless of the longitudinal position of the' worm on the shaft. To achieve this result, the worm shaft is formed with a second splined portion 18 arranged inwardly of the cylindrical portion 17 as shown. The interior of the worm is formed with an opening of the same cross section hexagonal, for example.

The outer end of the worm shaft projects from the fixed jaw as shown, and has secured thereto a head or knob 19 by which the shaft may be either rotated or shifted in the direction of its axis. As shown, the knob has a recess 20 within which the lower end of the splined shaft portion 12 fits, the shaft being further provided with a rivet portion 21 passed through an aperture in the center of the knob 19 and upset as shown at: 22 tofirmly secure the knob 19 in position on the shaft.

To hold the shaft 12 in desired inner or outerposition, corresponding to the locking and unlocking of the knurl, the shaft is provided with a recess 23 in which there is arranged an expansion spring 24 which, as shown, is in the form of a split ring of circular cross section. The spring 24 presses yieldably against the wall of "the lower portion 25 of the center aperture in the worm. As shown in Figs. 2 and 4, this wall is formed with inner and outer recesses 26 and 27 respectively. The spring 24 remains within the recess 23 regardless of the position of the worm shaft. However, it is capable of contracting when the knob 19 is shifted in an axial position so as to be capable of sliding along the wall 25. When it reaches'either recess 26 or recess 27, the spring expands automatically into the recess withoutdislodgement from the recess 23 so that the shaft is yieldingly held in the desired longitudinal position, corresponding to either the locking or the unlocking position of the shaft.

In operation,the worm shaft is normally in its outer position with the spring 24 in the recess 27 and with the cylindrical shaft portion 17 within the splined opening 14 in the fixed jaw. In this position, the worm shaft may be readily rotated to adjust the movable jaw 4- to its desired positions with respect to the fixed jaw 3. If the wrench is located so that the worm is not readily accessible, the knob 19 will in many instances be within reach so as'to permit the adjustment of the movable jaw by rotation of the knob. When it is desired to lock the movable jaw in adjusting position, the knob 19 is pushed inwardly so as to move the knurled shaft to bring the splined shaft portion 12 in locking engagement with the splined portion 14 of the aperture, the shaft being yieldably held in that position by the engagement of the spring 24 in the recess 26.

The modification shown in Fig. 7 is similar to that of the worm shaft is limited in this form of the invention by engagement of the spring 24 respectively with the shoulder 29 atthe inner end of the aperture 28 and with the wall 30 at the lower portion of the knurl opening 7 in the stationary jaw.

The modification shown in Fig. 8 is like that shown in Figs. 1 to 6 inclusive except that the retaining spring 24 is supported by the worm shaft to engage a convex curved wall 31 in the center aperture of the worm 8. The wall 31 is convex in a direction parallel to the axis of the worm shaft, so as to provide at the ends thereof recesses 32 and 33 into which the spring 24 expands to hold the worm shaft either in locked or unlocked position. As shown in Fig. 9, the splined locking portion 14a of the aperture in the fixed wall is formed with a number of corners which is a multiple of the number of corners of the splined shaft section 12. As shown, the splined aperture portion 14a is formed with 12 recesses 34 in which the six corners of the splined shaft portion 12 are designed to fit alternately. The recesses 34 have the same angular extent as the corners of the shaft spline, so that the side walls of the said corners rest against the walls of the said recesses. This arrangement provides for a very firm locking engagement between the spline portions 12 and 14a.

I claim: I

l. A wrench having a fixed jaw provided with a handle, a movable jaw supported by the fixed jaw, and formed with a rack, a worm shaft mounted in said fixed jaw for rotation and longitudinal movement, a worm carried bysaid shaft in engagement with'said rack to effect shifting of said movable jaw towards or away from said fixed jaw upon rotation of said worm, said worm being mounted on said shaft for relative movement longitudinally of the shaft and being held against rotation with respect to the shaft in all of its positions with respect to the shaft, means for locking said shaft against rotation in one of its longitudinal positions and in a plurality of angular positions thereof, said shaft having an end portion projecting from the stationary jaw and provided with means for rotating the shaft and worm when the shaft is in an unlocked position, and means arranged between said worm and said shaft for releasably holding said shaft in either locking or unlocking position.

2. A wrench having afixed jaw provided with a handle, a movable jaw supported by the fixed jaw and formed with a rack, a worm shaft mounted in said fixed jaw for rotation and longitudinal movement, a worm carried by said shaft in engagement with said rack to effect shifting of said movable jaw towards or awayfrom said fixed jaw upon rotation of said worm, said worm being mounted on said shaft for relative movement longitudinally of the shaft and being held against rotation with respect to the shaft throughout such longitudinal movement, said fixed jaw having an aperture provided with a locking spline, and said shaft having an inner cylindrical bearing portion supported in the fixed jaw, a splined portion engaging within said worm, a second splined portion movable into and out of locking engagement with said locking spline, and a cylindrical portion intermediate said splined portions movable into registry with said locking spline to permit rotation of said shaft and said worm, and means arranged between said'worm and said shaft for yieldingly holding said shaft in locked or unlocked position.

3. A wrench having a fixed jaw provided with a handle, a movable jaw supported by the fixed jaw and formed with a rack, a worm shaft mounted in said fixed jaw for rotation and longitudinal movement, a worm carried by said shaft in engagement with said rack to effect shifting of said movable jaw towards or away from said fixed jaw upon rotation of said worm, said worm being mounted on said shaft for relative movement longitudinally of the shaft and being held against rotation with respect to the shaft throughout such longitudinal movement, said shaft having an inner cylindrical bearing portion rotatably and slideably supported in the fixed jaw, and a splined locking portion, and said stationary jaw being formed with a shaft aperture having a splined locking portion and an enlarged cylindrical portion permitting free rotation of said splined shaft portion therein when the shaft is in one of its longitudinal positions with its locking portion in registry with the enlarged cylindrical portion of said aperture, and said splined aperture portion serving to lock said shaft against rotation when the shaft is in a longitudinal position with respect to the fixed jaw with the locking portion thereof in engagement with the locking portion of the aperture, and means for releasably holding said shaft in either locked or unlocked position. 4. A wrench having a fixed jaw provided with a handle, a movable jaw supported by the fixed jaw and formed with a rack, a worm shaft mounted in said fixed jaw for rotation and longitudinal movement, a worm carried by said shaft in engagement with said rack to eifect shifting of said movable jaw towards or away from said fixed jaw upon rotation of said worm, said worm being mounted on said shaft for relative movement longitudinally of the shaft and being held against rotation with respect to the shaft throughout such longitudinal movement, said shaft having an inner cylindrical bearing portion rotatably and slidably supported in the fixed jaw, and a splined locking portion, and said stationary jaw being formed with a shaft aperture having a splined portion and an enlarged cylindrical portion permitting free rotation of said splined shaft portion therein when the shaft is in one of its longitudinal positions, and said splined aperture portions serving to coact with the locking portion of said shaft to lock said shaft against rotation when the shaft is in another longitudinal position with respect to the fixed jaw, and means arranged between said worm and said shaft for releasably holding said shaft in a longitudinal position, said shaft having also an outer end portion projecting -rom the stationary jaw and provided with means for shifting the shaft longitudinally and for rotating the shaft when the shaft is in an unlocked position. 7

References Cited in the file of this patent UNlTED STATES PATENTS OTHER REFERENCES American Machinist, page 221, Oct. 26, 1953. in Division 29.) 

